There were shouts of joy in the mission control room at the Jet Propulsion Laboratory in Pasadena, California, as Pathfinder, with its valuable "Mars Buggy" cargo, ended its epic, 309-million mile (497million km) journey by landing on the planet just after 6pm BST.
The spacecraft surprised scientists by almost immediately transmitting signals they were not expecting to hear for hours. Further cheering broke out among the Pasadena controllers when Pathfinder successfully deployed itself and the first data arrived on their computer screens shortly after 10.20pm British time. President Bill Clinton hailed the landing, saying: "Our return to Mars today marks the beginning of a new era in the nation's space exploration programme."
His vice-president, Al Gore, telephoned members of the team to congratulate them on the success of the mission. "What a great way to celebrate America's birthday," he said.
And Brian Muirhead, the flight systems manager, confirmed Pathfinder's success in beaming back to earth was way beyond their expectations: "It has been exceptional. I don't think any of us expected it to go the way it has." The landing and deployment of the craft had gone "perfectly," he said.
The Mars Pathfinder rocket, containing a tiny six-wheeled Mars rover, fell at a speed of about 90kph through the thin atmosphere, inflating four giant airbags when about 80 metres above the ground, and firing retro- rockets before bouncing up to 200 metres off the surface for up to five minutes before stopping. It then spent three hours deflating its airbags and unfolding the three petals which encase its eyes and sensors. A camera perched on a mast was programmed to make a 360 degree sweep of the surroundings to help assess when to let the 10kg Sojourner rover roll out across the dusty, rocky plains of the Ares Vallis flood plain.
In a masterpiece of timing, the television signals beamed back from the rover - showing everything from Pathfinder's solar panels to the distant horizon - were due to arrive early evening, just in time for Americans to lap up the first live pictures from the Red Planet. All being well, live pictures were due to be shown on BBC2 this morning from 8am-10am. Sojourner will move about at just under 1.13 cm per second. It will take pictures and examine minerals in the rocks and soil; Pathfinder, meanwhile, will enjoy the view, sending back pictures and data on the atmosphere.
Donna Shirley, the mission's manager, said that although Mars is popularly known as the Red Planet, its sunrise could be blue. "We know a lot about the atmosphere of Mars, but this will tell us more as this is only the third time the atmosphere has been bored," she said.
Red letter day
Pathfinder is the first US spacecraft dispatched to Mars - the Red Planet - since the $1bn (pounds 600m) Mars Observer vanished from Nasa radar screens in August 1993. It is the first mission designed to land there since the Viking 2 probes set down in 1976.
Those excited last year by apparent traces of life in a Martian meteorite should not build their hopes up - the rover is not sophisticated enough to detect anything hidden deep beneath the surface.
European space experts are monitoring the American mission to learn lessons that might help their plans to send a spacecraft to Mars in 2003.Reuse content